The subject matter disclosed herein generally relates to apparatus for transferring energy between a rotating element and fluid, and more specifically to turbomachinery, for example, centrifugal compressors.
Conventional turbomachinery, for example centrifugal compressors, generally include a plenum configured to direct a working gas (e.g., air, natural gases, hydrocarbons, carbon dioxide, or the like) from an inlet to one or more impellers to facilitate transferring energy from the impellers to the working gas. To direct the flow of the working gas through the plenum and towards the impellers in a desired flow path, a number of inlet guide vanes are disposed symmetrically within the plenum. In some variations, to correct an inlet swirl to the compressor caused by a variation in mass flow each of the inlet guide vanes may be rotated about its axis, thereby improving operation. However, the inventors have observed that such configurations of the inlet guide vanes introduce losses into the plenum, thereby negatively affecting compressor performance and reducing efficiency of the compressor.
Therefore, the inventors have provided an improved apparatus for transferring energy between a rotating element and fluid.